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Hi. I wanted to know if i can prevent or redirect the smoke that is exhausted from my rockets left valve cover. The smoke is coming out from kind of a filter, as shown on the photo. It smells bad in the cabin. It is also dripping oil. Can anything be done about it except replacing rings?
Well a leak down test will tell you exactly what cylinder is leaking and where. If its pushing oil that far i gonna say its gotta have a broken ring but the leak down tester will tell you whats what
Its probably blowby, not uncommon in older engines. He needs a PCV and possibly a breather with a nipple to run a hose to the air cleaner like this to replace the atmospheric one he currently has.
It all depends on how much blow-by the engine has. The better the piston rings seal, the less blow-by produced.
The right term for it is not "smoke" but blow-by; when combustion gases escape out of the combustion chamber past the piston during the power stroke and exiting out the breather when there no PCV is used or if there is more then the PCV can handle.
Thanks for all. Hallow again eric.* I think I do have a pcv (or I don’t?). I added photos of the two valve covers. The right cover is connected with a hose under the carburetor. *Does it looks o.k?
Another question I have is about lowering the front by cutting the coil springs. Does anyone know what is the stock height of 1974 cutlass supreme coupe
?
On my 72 Vista, I run the passenger side breather element to the air cleaner and the driver's side pcv goes back into the carb.
That's how it was set up, at least, when I bought the car, so I just left it like that. I only ever had problems with fumes once when that pcv on the driver's side literally just fell apart. Who knows? It was probably 42 years old anyway.
I don't see much oil residue dripping from that filter, which is good, but I can see lots of crud coming directly off of the breather element, which could indicate that it is just long gone and you need a new one. Those are cheap from rockauto.com.
Last edited by Arrowstorm; Sep 13, 2016 at 11:05 AM.
Also, did you have the valve covers off recently? Is it just me, or is that valve cover missing a few bolts?! I would suspect a cap between mating surfaces might also account for a bit of those fumes you're smelling.
Thanks for all. Hallow again eric.* I think I do have a pcv (or I don’t?). I added photos of the two valve covers. The right cover is connected with a hose under the carburetor. *Does it looks o.k?
The right cover looks fine.
Another question I have is about lowering the front by cutting the coil springs. Does anyone know what is the stock height of 1974 cutlass supreme coupe
?
Remove the short hose and filter and run a hose to the bottom of your air cleaner, you may need to purchase a fitting for the air cleaner.
Originally Posted by ilanzo
I added another pic. Of the hose under the carb.that is connecred to the head cover And marked something that looks like broken hose connection.
This looks like you have a later carb where the adjustment used to be blocked off with a small plug that was drilled out to gain access. There should be a similar hole under the fuel filter.
Yes you can cut the spring shorter, its usually trial and error a 1/2 coil at a time.
Do what Eric says, get the proper fitting, and connect the breather intake to the air cleaner, like it was designed.
Also, confirm that your PCV valve is working properly (or just replace it), and confirm that the hose to the PCV valve is clear (they can become filled with gunk), and that it has full engine vacuum.
I'm surprised nobody else has mentioned it; however, you need to remove the hose in your third picture from the front of your carburetor (the one that is circled in green) and replace it with a proper vacuum cap. A length of rubber hose with a screw in it is a vacuum leak waiting to happen.
I also agree with the Erics... get the proper fitting for your driver's side valve cover and run it to your air cleaner. If you can't live without a "hot rod" style breather then ditch the factory elbow in your driver's side valve cover and run the breather directly on the valve cover.
Finally you can check the PCV valve in your passenger side valve cover by removing it from the valve cover with the vacuum line still attached (while the engine is running) and covering it with your thumb. You will hear and feel the PCV valve actuate when you plug the vacuum leak. If it doesn't actuate or feels stuck spend a few bucks and buy a new one or at least clean the one you have.